A 22-year-old man was arrested Monday for the beating death of a Patas monkey at Zoo Boise that's gained national attention.

Michael J. Watkins, of Weiser, is accused of killing the male monkey during a burglary at the zoo early Saturday. He's in the Washington County Jail on felony burglary and grand theft charges. The theft charge relates to the death of the monkey.

A second man believed to have waited outside the zoo while Watkins broke in has been identified but is not facing charges, said Boise police Chief Mike Masterson at a press conference Monday night.

The case has sparked outrage around the country.

A tip to Crime Stoppers on Sunday led police to identify Watkins as a suspect. Police connected the tip to an investigation that occurred Saturday morning when a man reported to a local hospital with injuries. That man was Watkins, and police realized his injuries may be connected to the break in and monkey attack.

"The story did not seem to mesh with the injuries," Masterson said. Police have not said if they know of a possible motive for the burglary or if they know why the monkey was killed. Masterson said more details will be released as Watkins' case proceeds in 4th District Court.

Detectives plan to submit their investigation to Ada County prosecutors on Tuesday.

"I know the community demands and deserves answers to the many questions surrounding this senseless crime," Masterson said. "This case is long on emotion and short on facts for the time being."

Police responded to the zoo about 4:30 a.m. after a security guard spotted two men near the primate exhibit. One was inside the fence, the other was out. The men fled, but police found a hat they believed one had left behind. That hat belongs to Watkins, Masterson said Monday. Authorities were searching the zoo for the thieves when they heard groaning and found the monkey badly injured outside his cage.t. He was treated by the zoo's veterinarian but died a short time later of blunt force trauma to his head and neck.

Zoo Director Steven Burns praised the arrest at Monday's press conference. He said the monkey's death devastated his staff and has garnered an "amazing amount" of attention across the country.

"When I told the zoo staff what had happened, they were in disbelief. They were confused. They were angry. They weren't quite sure what to do," Burns said. "But they held it together. We have 300 animals at the zoo, and they recognize that they are needed to continue take care of the animals that are still there."

Burns also thanked the community for what he described as an outpouring of support.

"Monkeys are one of the most popular animals at the zoo," Burns said. "It's difficult for parents to have to explain why something like would happen."

The monkey shared space with another Patas monkey. Monkeys are social animals that need to be housed with other monkeys. Burns said staff is looking for another monkey to move to Boise.

"He was unharmed in all of this, but he is by himself right now so we're making sure that he's OK and giving him some extra attention," Burns said. "For the short time, he is OK being by himself right now, but that's not a long-term solution."

Police say Watkins overcame several security measures to get inside the zoo but declined to provide details.The zoo was re-accredited by the Association of Zoos & Aquariums last fall, which requires an updated security plan. Officers collected blood from the scene but aren't sure if it belongs to Watkins or the monkey, Masterson said. Lab test results are expected to take weeks. Masterson said Watkins had injuries on his upper torso, but police have not yet determined how he got them.

Boise police traveled to Weiser Monday to arrest Watkins, who Masterson said was taken into custody about 2 p.m.

Watkins has misdemeanor drug- and driving-related convictions in Payette County in 2009, according to state court records. He violated his probation in that case at least once and was ordered in June to serve time in jail.

The investigation is ongoing, but no other suspects are expected to be charged, Masterson said. Masterson said the second man is believed to live in the area. He believes Watkins was in Boise visiting friends. Asked if they believe Watkins was intoxicated, Masterson said, "it's Saturday morning at 4:30. You know downtown life as well as we do. But we do not have specific evidence of that at this point."

The monkeys arrived in Boise three years ago from the Lowry Park Zoo in Tampa Bay, Fla.